The present invention relates to an image forming apparatus such as a printer, or the like and, more particularly, to an image forming apparatus equipped with a developing unit storage device capable of storing a plurality of developing units.
Some image forming apparatuses of this type comprise a plurality of developing units, and switch these developing units by a rotary mechanism.
Another apparatus is proposed wherein a plurality of developing units are equipped in a storage device outside a main body. In this case, a moving operation is required to replace a developing unit inside the main body with a developing unit inside the storage device, or to move a developing unit inside the storage device into the main body.
In such an apparatus, since the main body and the storage device can store a plurality of developing units, the colors of the stored developing units are preferably precisely detected, and an operator preferably easily identifies the colors to improve operability.
In the apparatus of the type which stores the developing units outside the main body, if the main body and a developing unit storage device outside the main body independently recognize the storage states of the developing units, they must be handled as separate apparatuses, resulting in cumbersome operations.
In addition, the main body or the storage device outside the main body must, have at least one empty storage section not storing a developing unit. If not so, the developing units will never be moved and exchanged.